diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/mutex_w32.c | 16 | ||||
| -rw-r--r-- | src/os_unix.c | 1 | ||||
| -rw-r--r-- | src/os_win.c | 20 |
3 files changed, 14 insertions, 23 deletions
diff --git a/src/mutex_w32.c b/src/mutex_w32.c index 7b411018f..7eb5b50be 100644 --- a/src/mutex_w32.c +++ b/src/mutex_w32.c @@ -314,12 +314,22 @@ static int winMutexTry(sqlite3_mutex *p){ /* ** The sqlite3_mutex_try() routine is very rarely used, and when it ** is used it is merely an optimization. So it is OK for it to always - ** fail on some platforms. But - it is required for ENABLE_SETLK_TIMEOUT - ** builds. + ** fail. + ** + ** The TryEnterCriticalSection() interface is only available on WinNT. + ** And some windows compilers complain if you try to use it without + ** first doing some #defines that prevent SQLite from building on Win98. + ** For that reason, we will omit this optimization for now. See + ** ticket #2685. */ #if defined(_WIN32_WINNT) && _WIN32_WINNT >= 0x0400 assert( winMutex_isInit==1 ); - if( sqlite3_win32_is_nt() && TryEnterCriticalSection(&p->mutex) ){ + assert( winMutex_isNt>=-1 && winMutex_isNt<=1 ); + if( winMutex_isNt<0 ){ + winMutex_isNt = sqlite3_win32_is_nt(); + } + assert( winMutex_isNt==0 || winMutex_isNt==1 ); + if( winMutex_isNt && TryEnterCriticalSection(&p->mutex) ){ #ifdef SQLITE_DEBUG p->owner = tid; p->nRef++; diff --git a/src/os_unix.c b/src/os_unix.c index 77855a8dd..b1996278c 100644 --- a/src/os_unix.c +++ b/src/os_unix.c @@ -4290,6 +4290,7 @@ static int unixGetpagesize(void){ ** ** nRef ** +** The following fields are read-only after the object is created: ** ** hShm ** zFilename diff --git a/src/os_win.c b/src/os_win.c index a02b0c535..c042ac162 100644 --- a/src/os_win.c +++ b/src/os_win.c @@ -3874,25 +3874,6 @@ static int winShmMutexHeld(void) { ** Either winShmNode.mutex must be held or winShmNode.nRef==0 and ** winShmMutexHeld() is true when reading or writing any other field ** in this structure. -** -** aMutex[SQLITE_SHM_NLOCK]: -** Normally, when SQLITE_ENABLE_SETLK_TIMEOUT is not defined, mutex -** winShmNode.mutex is used to serialize calls to the xShmLock() -** method. -** -** For SQLITE_ENABLE_SETLK_TIMEOUT builds, xShmLock() only takes the -** mutexes in the aMutex[] array that correspond to locks being taken -** or released. This means that: -** -** * Modifying the winShmNode.pFirst list requires holding *all* -** the locks in the aMutex[] array. -** -** * Reads and writes to winShm.sharedMask and winShm.exclMask must -** use AtomicLoad() and AtomicStore(). This is because it may be -** read by other threads while it is being modified. -** -** TODO: winShmNode.mutex is held for the space of time when LockFileEx() -** is called on winShmNode.hFile. */ struct winShmNode { sqlite3_mutex *mutex; /* Mutex to access this object */ @@ -3913,7 +3894,6 @@ struct winShmNode { int nRef; /* Number of winShm objects pointing to this */ winShm *pFirst; /* All winShm objects pointing to this */ winShmNode *pNext; /* Next in list of all winShmNode objects */ - #if defined(SQLITE_DEBUG) || defined(SQLITE_HAVE_OS_TRACE) u8 nextShmId; /* Next available winShm.id value */ #endif |